Are we being manipulated by microbes? The idea is not so whacky. We know that a wide range of microscopic parasites have evolved the ability to manipulate their hosts, even to the point of making the host behave in strange ways. A well-known example is Toxoplasma gondii, a protozoan whose life cycle begins inside a... Read More

Incidence of chlamydia, a major cause of infertility. The high polygyny rate among the “female farming” peoples of sub-Saharan Africa may have favored the evolution of STDs. Is this where we should look for the precursor of the hypothetical “gay germ”? (source) Heritability for male homosexuality is low to moderate (30 to 45%). There is... Read More

Squamous cervix cells covered with rod-shaped bacteria, Gardnerella vaginalis(source) Bacterial vaginosis is a common disease among reproductive-aged women: Its incidence correlates with the number of lifetime sex partners, and this correlation holds true even when one controls for a series of socioeconomic variables: poverty, smoking, body mass index, douching frequency, education, and oral contraceptive use... Read More